Trunks did it. He finally killed the Androids and Cell. His timeline was safe. He knew Gohan would be proud and he has to keep training so he won't let this peace go to waste. However one day when he was flying to a grave that he made for Gohan. He saw someone looking at it. So he landed on the ground.

Trunks Briefs: "Did you know Gohan? Not many people visit this area except for me and sometimes my mom. So it's odd seeing a new face here. What brings you here."